2,5-Dibromopyridine Property

Melting point:

92-95 °C (lit.)

Boiling point:

235 °C / 772mmHg

Density 

2.0383 (rough estimate)

refractive index 

1.5800 (estimate)

Flash point:

62℃

storage temp. 

Inert atmosphere,Room Temperature

solubility 

Chloroform (Slightly), Methanol (Slightly)

pka

-1.57±0.10(Predicted)

form 

Crystalline Powder

color 

Almost white or light beige to brown

Water Solubility 

insoluble

BRN 

109099

InChI

InChI=1S/C5H3Br2N/c6-4-1-2-5(7)8-3-4/h1-3H

InChIKey

ZHXUWDPHUQHFOV-UHFFFAOYSA-N

SMILES

C1(Br)=NC=C(Br)C=C1

CAS DataBase Reference

624-28-2(CAS DataBase Reference)

Safety

Hazard Codes 

Xi,Xn

Risk Statements 

36/37/38-20/21/22

Safety Statements 

26-37/39-36/37/39-36

RIDADR 

UN2811

WGK Germany 

3

HazardClass 

IRRITANT

HS Code 

29333999

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P270Do not eat, drink or smoke when using this product.

P271Use only outdoors or in a well-ventilated area.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P304+P340IF INHALED: Remove victim to fresh air and Keep at rest in a position comfortable for breathing.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

P405Store locked up.

P501Dispose of contents/container to..…

2,5-Dibromopyridine Chemical Properties,Usage,Production

Description

Pyridine and its derivatives are distributed widely by nature. Many plant constituents are as contain pyridine ring compounds in the structure of alkaloids, etc.; they are the bases producing many vital compounds and are indispensable raw materials during medicine, agricultural chemicals, dyestuff, tension-active agents, rubber ingredients, fodder additives, foodstuff additives, tackiness agents, etc. are produced.2,5-dibromo pyridine is an important intermediate of organic synthesis and is mainly used in medicine intermediate, organic synthesis, and organic solvent, can also be applicable to aspects such as DYE PRODUCTION, pesticide production and spices. Selective monolithiation of 2,5-dibromopyridine at either the 2-position or the 5-position is reported. Solvent and concentration strongly influence the selectivity. Coordinating solvents and higher concentration favour the 5-position, while non-coordinating solvents and lower concentration favour the 2-position[1].

Chemical Properties

2,5-Dibromopyridine is an off-white crystalline solid. It is insoluble in water but soluble in strong polar organic solvents. It exhibits strong alkalinity.

Uses

2,5-Dibromopyridine (cas# 624-28-2) is a compound useful in organic synthesis.

Preparation

To synthesize 2,5-dibromopyridine, follow these steps:
Add 2-amino-5-bromopyridine (13.0 kg) into a water-cooled solution at 10 °C.
Slowly add 47% aqueous hydrogen bromide (37 L) to the mixture.
Introduce liquid bromine (11 L) into the mixture.
Maintain the reaction temperature below 10 °C.
Prepare a solution of NaNO2 (16.1 kg) and H2O (19 L) and add it dropwise to the mixture while keeping the temperature between 0-5 °C.
Stir the reaction mixture for 30 minutes.
Treat the mixture with a solution of NaOH (28.0 kg) in water (30 L) at a controlled rate below 20-25 °C.
Extract the reaction mixture with diethyl ether (3 × 40 L).
Dry the organic layer with anhydrous Na2SO4.
Remove the desiccant by filtration.
Evaporate the resulting filtrate under reduced pressure to dryness.
Suspend the residue in heptane (10 L).
Collect the target product molecule, 2,5-dibromopyridine, by filtration.
Synthesis method of 2,5-dibromopyridine

References

[1] Xin Wang. “Selective monolithiation of 2,5-dibromopyridine with butyllithium.” Tetrahedron Letters 41 1 (2000): 4335–4338.